Multiple Probes of Dark Matterin Early-type Galaxies

Multiple Probes of Dark Matterin Early-type Galaxies

Aaron J. RomanowskyUniv. California ObservatoriesAaron J. RomanowskyUniv. California Observatories

field stars (integrated light)field stars (integrated light)

planetary nebulaeplanetary nebulae

globular clustersglobular clusters

X-ray gasX-ray gas(N.Douglas et al.)(N.Douglas et al.)

(J. Brodie et al.)(J. Brodie et al.)

335 nearby galaxies (Prugniel & Simien 1996):I(R), �Ap(R)

Assume �(r)~ r -2, solve Jeans eqns for Mdyn(< Reff)

335 nearby galaxies (Prugniel & Simien 1996):I(R), �Ap(R)

Assume �(r)~ r -2, solve Jeans eqns for Mdyn(< Reff)

(Tortora et al. 2009)(Tortora et al. 2009)

Model UBVRI using SSP (Bruzual & Charlot 2003)

with SF history e-t/τ, Chabrier IMF → M*

Model UBVRI using SSP (Bruzual & Charlot 2003)

with SF history e-t/τ, Chabrier IMF → M*

MDM = Mdyn - M*MDM = Mdyn - M*

M/Ldyn ~ L0.21, M/L* ~ L0.06

� most of Fundamental Plane “tilt”driven by DM (or IMF) !

M/Ldyn ~ L0.21, M/L* ~ L0.06

� most of Fundamental Plane “tilt”driven by DM (or IMF) !

Dark matter in early-type centersDark matter in early-type centers

(also Graves 2009; but contrast Jun & Im 2008; Hudson et al., this conference)(also Graves 2009; but contrast Jun & Im 2008; Hudson et al., this conference)

SSPSSP

dynamicsdynamics

Central dark matter fractions (cont’d)Central dark matter fractions (cont’d)

(Tortora et al. 2009)(Tortora et al. 2009)

fDM increases with luminosity, no clear dependence on galaxy sub-type(cf. Cappellari et al. 2006)

fDM increases with luminosity, no clear dependence on galaxy sub-type(cf. Cappellari et al. 2006)

central DM density roughly follows ΛCDM expectations, modulo uncertain

concentrations and virial masses

central DM density roughly follows ΛCDM expectations, modulo uncertain

concentrations and virial masses

Tortora et al. (2009) dataTortora et al. (2009) data

ΛCDM toy models, �SF(M*)

ΛCDM toy models, �SF(M*)

fDM � 1 - ϒ* / ϒdyn

Thomas et al. (2009) dataThomas et al. (2009) data

Linking dark matter and star formationLinking dark matter and star formation

(Tortora et al. 2009 � Napolitano et al. 2009b)(Tortora et al. 2009 � Napolitano et al. 2009b)

fDM in early-types decreases with stellar age and τ(at const M*)

Some effect of age-size correlation

fDM in early-types decreases with stellar age and τ(at const M*)

Some effect of age-size correlation

� adiabatic contraction strengthens with time, while�SF � M*/(fb Mtot)decreases?

(lumpy, efficient, protracted star formation at early times??)

� “DM upsizing” ?

� adiabatic contraction strengthens with time, while�SF � M*/(fb Mtot)decreases?

(lumpy, efficient, protracted star formation at early times??)

� “DM upsizing” ?

�SF =0.1�SF =0.1

�SF =0.3�SF =0.3�SF =0.7�SF =0.7

Critical constraints at larger radiiCritical constraints at larger radii

(Navarro et al. 1997; Gnedin et al. 2004; Maccio et al. 2008; Tortora et al. 2009)

(Navarro et al. 1997; Gnedin et al. 2004; Maccio et al. 2008; Tortora et al. 2009)

� need mass to <~ 20% at 5 Reff

� need mass to <~ 20% at 5 Reff

L* elliptical with NFW halo, 2-σ cvir scatterWith adiabatic contractionL* elliptical with NFW halo, 2-σ cvir scatterWith adiabatic contraction

� account for full triaxialorbit structure

� account for full triaxialorbit structure

� hardest systems for measuring DM??

� hardest systems for measuring DM??

DM from extended SAURON kinematicsDM from extended SAURON kinematics

(Maccio et al. 2008;De Lorenzi et al. 2009)(Maccio et al. 2008;De Lorenzi et al. 2009)

� DM density within 10 kpc looks normal for WMAP5 ΛCDMwith no AC

� DM density within 10 kpc looks normal for WMAP5 ΛCDMwith no AC

NGC 3379 and NGC 821 (Weijmans et al. 2009): • two L* fast rotators w/kinematics to 3-4 Reff• axisymmetric, quasi-triaxial Schwarzschild models• maximum stellar mass assumed!

NGC 3379 and NGC 821 (Weijmans et al. 2009): • two L* fast rotators w/kinematics to 3-4 Reff• axisymmetric, quasi-triaxial Schwarzschild models• maximum stellar mass assumed!

GC dynamics in NGC 1407GC dynamics in NGC 1407

172 GC velocities from LRIS, DEIMOSto 60 kpc (10 Reff)(Cenarro et al. 2007; Romanowsky et al. 2009)+ ~150 new velocities

to be analyzed…

172 GC velocities from LRIS, DEIMOSto 60 kpc (10 Reff)(Cenarro et al. 2007; Romanowsky et al. 2009)+ ~150 new velocities

to be analyzed…

E1, MB = -21.0,Group centralgalaxy (GCG),D = 21 Mpc

E1, MB = -21.0,Group centralgalaxy (GCG),D = 21 Mpc

Mvir~1014 MSungroup M/LB ~ 800→ “dark cluster” (cf. Gould 1993)

Mvir~1014 MSungroup M/LB ~ 800→ “dark cluster” (cf. Gould 1993)

Modeling discrete velocitiesModeling discrete velocitiesBinning (in R,v) loses informationLikelihood fcn

200 velocities: mass recovered at ~20% in axisymmetric const-M/L system200 velocities: mass recovered at ~20% in axisymmetric const-M/L system

Chanamé et al. (2008)Chanamé et al. (2008)

Schwarzschild orbit model fit of stellar + GC kinematics in M87(Romanowsky & Kochanek 2001)

Unbinned LOSVD fitting, shown in bins: model / data / data composite

Schwarzschild orbit model fit of stellar + GC kinematics in M87(Romanowsky & Kochanek 2001)

Unbinned LOSVD fitting, shown in bins: model / data / data composite

Multiple probes to reduce mass-anisotropy degeneracyMultiple probes to reduce mass-anisotropy degeneracy

Require consistent solution for GC subsystem

(Romanowsky et al. 2009)

Require consistent solution for GC subsystem

(Romanowsky et al. 2009)

starsstars GCsGCs

Stars or GCs alone do not rule out �(r)~ r -2

but used jointly they do…(Romanowsky & Kochanek 2001)

Stars or GCs alone do not rule out �(r)~ r -2

but used jointly they do…(Romanowsky & Kochanek 2001)

NGC 1407NGC 1407M87M87

metal-poor GCsmetal-poor GCs

metal-rich GCsmetal-rich GCs

NGC 1407 mass profile: X-rays vs GCsNGC 1407 mass profile: X-rays vs GCs

discrepant at 2 �(cf. high-cvir, low ϒ*found by Humphrey et al. 2006)

discrepant at 2 �(cf. high-cvir, low ϒ*found by Humphrey et al. 2006)

Humphrey et al. (2006)Humphrey et al. (2006)

GC kinematics from DEIMOS,X-ray mass from Chandra

GC kinematics from DEIMOS,X-ray mass from Chandra

(Romanowsky et al. 2009; R. Johnson, 2009, Ph.D. Thesis)

NGC 1407 mass profile: X-rays vs GCsNGC 1407 mass profile: X-rays vs GCs

discrepant at 2 �(cf. high-cvir, low ϒ*found by Humphrey et al. 2006)

discrepant at 2 �(cf. high-cvir, low ϒ*found by Humphrey et al. 2006)

What �(r) for GCs required for consistency?

What �(r) for GCs required for consistency?

X-raytheory

isotropic

radial

tangential

GC kinematics from DEIMOS,X-ray mass from Chandra

GC kinematics from DEIMOS,X-ray mass from Chandra

(Romanowsky et al. 2009; R. Johnson, 2009, Ph.D. Thesis)

Chandra study implies extensive DM halos(Humphrey et al. 2006)Chandra study implies extensive DM halos(Humphrey et al. 2006)

But “shoulders” seen in some mass profiles (e.g. Zhang et al. 2007)

But “shoulders” seen in some mass profiles (e.g. Zhang et al. 2007)

N1407N1407

�CDM halo fits to X-ray data overpredicthalo concentrations to compensate�CDM halo fits to X-ray data overpredicthalo concentrations to compensate

Cross-checks with stellar, GC dynamics(Bridges et al. 2006; Romanowsky et al. 2009; Gebhardt & Thomas 2009; Johnson et al. 2009; Schuberth et al. 2009)

All cases: mass discrepancies � 40%→ non-thermal pressure support

+ non-equilibrium gas?→ X-ray deprojection instability?

(Humphrey et al. 2009)

Cross-checks with stellar, GC dynamics(Bridges et al. 2006; Romanowsky et al. 2009; Gebhardt & Thomas 2009; Johnson et al. 2009; Schuberth et al. 2009)

All cases: mass discrepancies � 40%→ non-thermal pressure support

+ non-equilibrium gas?→ X-ray deprojection instability?

(Humphrey et al. 2009)

X-ray mass profiles of galaxies/groupsX-ray mass profiles of galaxies/groups

M60M60

N1399N1399

M87 M87

N4636N4636

PN vs GC dispersions in fast rotators

3/4 cases: PNe, GCssimilar dispersions3/4 cases: PNe, GCssimilar dispersions

GC data from Gemini/GMOS, Keck/DEIMOS (Romanowsky, Brodie, Faifer, Forbes, Foster, Richtler, Schuberth, Spitler, Strader; Mendez et al. 2001; Coccato et al. 2009)

GC data from Gemini/GMOS, Keck/DEIMOS (Romanowsky, Brodie, Faifer, Forbes, Foster, Richtler, Schuberth, Spitler, Strader; Mendez et al. 2001; Coccato et al. 2009)

Independent mass results in NGC 4697

�PN(r) = 0.7 r / (r+ 6.3 kpc)

GCs more sensitive than PNeto halo mass because more radially extended

GCs prefer low-concentration halo

Crude spherical model for PNegives same results as sophisticated flattened model!(De Lorenzi et al. 2008)

�GC = -0.5

Early-type halo velocity profilesEarly-type halo velocity profiles• Bimodality in PN velocity dispersions

(Coccato et al. 2009)

• GCs similar but less dramatic

• Bimodality in PN velocity dispersions

(Coccato et al. 2009)

• GCs similar but less dramatic

fast

slow

Slow rotators: flat/rising vc(group-scale halos?)

Fast rotators: declining vc(Romanowsky & Kochanek 2001; Romanowsky et al. 2003; Côté et al. 2003; Schuberth et al. 2006; Douglas et al. 2007; Richtler et al. 2008; De Lorenzi et al. 2008, 2009; Napolitano et al. 2009); Kumar et al. in prep.; Romanowsky et al. in prep)

Slow rotators: flat/rising vc(group-scale halos?)

Fast rotators: declining vc(Romanowsky & Kochanek 2001; Romanowsky et al. 2003; Côté et al. 2003; Schuberth et al. 2006; Douglas et al. 2007; Richtler et al. 2008; De Lorenzi et al. 2008, 2009; Napolitano et al. 2009); Kumar et al. in prep.; Romanowsky et al. in prep)

Mass/anisotropy comparisons

→ signature of multiple mergers ?!(not in Sommer-Larsen 2006: β ~ 0.6-0.8)→ signature of multiple mergers ?!(not in Sommer-Larsen 2006: β ~ 0.6-0.8)

Fast rotator binary merger simulations (Dekel et al. 2005)

• high DM content, radial orbits

Fast rotator star/PN observations• low DM content, radial orbits

Slow rotator PN/GC observations• very high DM content,

isotropic orbits

DM trends of early-type galaxiesDM trends of early-type galaxies

Systematic difference between slow rotators and fast rotators + late-types

Systematic difference between slow rotators and fast rotators + late-types

�CDM prediction is “forbidden region”!�CDM prediction is “forbidden region”!(Napolitano et al. 2009)(Napolitano et al. 2009)

Predicted concentrations:Maccio et al. (2008)Predicted concentrations:Maccio et al. (2008)

NB: dichotomy not confirmed in central studies NB: dichotomy not confirmed in central studies (Tortora et al. 2009; Barnabè et al. 2009; Thomas et al. 2009; but see Cappellari et al. 2006)(Tortora et al. 2009; Barnabè et al. 2009; Thomas et al. 2009; but see Cappellari et al. 2006)

Halo sequences differ by factor of ~20 in ρse.g. zc ~ 4 vs 1

Halo sequences differ by factor of ~20 in ρse.g. zc ~ 4 vs 1

(McGaugh et al. 2007; Mandelbaum et al. 2008)(McGaugh et al. 2007; Mandelbaum et al. 2008)

Dark matter bimodality from galaxy formation physics?Dark matter bimodality from galaxy formation physics?

Mechanisms for increasing central DM density:• adiabatic halo contraction (why slow rotators?)• dry mergers � equipartition: slow rotators (Ruszkowski & Springel 2009)

Mechanisms for increasing central DM density:• adiabatic halo contraction (why slow rotators?)• dry mergers � equipartition: slow rotators (Ruszkowski & Springel 2009)

Mechanisms for decreasing central DM density:• starburst blowout (Gnedin & Zhao 2002; Mo & Mao 2004)

• satellite mergers: angular momentum transfer by dynamical friction – when satellites less susceptible to SN feedback (slow rotators??)(El-Zant et al. 2001, 2004; Nipoti et al. 2004; Gao et al. 2004; Tonini et al. 2006; Dutton et al. 2007; Romano-Diaz et al. 2008, 2009; Jardel & Sellwood 2009; Johansson et al. 2009; Pedrosa et al. 2009)

• clumpy gas inflow (Dutton et al. 2007; Abadi et al. 2009)

• gravitational coupling of SN winds to DM (Mashchenko et al. 2006, 2008)

• bar-driven dynamical friction (Weinberg & Katz 2002; Sellwood 2008; Dubinski et al. 2009)

Mechanisms for decreasing central DM density:• starburst blowout (Gnedin & Zhao 2002; Mo & Mao 2004)

• satellite mergers: angular momentum transfer by dynamical friction – when satellites less susceptible to SN feedback (slow rotators??)(El-Zant et al. 2001, 2004; Nipoti et al. 2004; Gao et al. 2004; Tonini et al. 2006; Dutton et al. 2007; Romano-Diaz et al. 2008, 2009; Jardel & Sellwood 2009; Johansson et al. 2009; Pedrosa et al. 2009)

• clumpy gas inflow (Dutton et al. 2007; Abadi et al. 2009)

• gravitational coupling of SN winds to DM (Mashchenko et al. 2006, 2008)

• bar-driven dynamical friction (Weinberg & Katz 2002; Sellwood 2008; Dubinski et al. 2009)

Need self-consistent picture from orbits + other cluesNeed self-consistent picture from orbits + other clues

(Not readily explainable by halo bias, WDM, MOND, etc.?)(Not readily explainable by halo bias, WDM, MOND, etc.?)

• Fundamental plane “tilt” from dark matter;DM “upsizing” with time?

• PN.S/SLUGGS surveys of global (esp. halo) properties of nearby early-type galaxies

• Stars vs PNe, PNe vs GCs, GCs vs GCs: general agreement on mass profiles

• X-ray/optical mass profile discrepancies

• dark matter bimodality: different assembly physics?

•• Fundamental plane Fundamental plane ““tilttilt”” from dark matter;from dark matter;DM DM ““upsizingupsizing”” with time?with time?

•• PPN.SN.S//SLUGGSSLUGGS surveys of global (esp. halo) surveys of global (esp. halo) properties of nearby earlyproperties of nearby early--type galaxiestype galaxies

•• Stars Stars vsvs PNePNe, , PNePNe vsvs GCs, GCs GCs, GCs vsvs GCs: GCs: general agreement on mass profilesgeneral agreement on mass profiles

•• XX--ray/optical mass profile discrepanciesray/optical mass profile discrepancies

•• ddark matter bimodality: ark matter bimodality: different assembly physics?different assembly physics?